Following her father's puzzling disappearance, Kate and her city-bred companions brave the untamed backwoods in a desperate search for him. However, the harsh environment becomes a dangerous catalyst for their explosive mix of personalities, propelling them into a world of raw emotion and unbridled passion.

Orbiting a quiet backwater planet, the massed forces of the universe's deadliest species gather, drawn to a mysterious message that echoes out to the stars. And amongst them, the Doctor. Rescuing Clara from a family Christmas dinner, the Time Lord and his best friend must learn what this enigmatic signal means for his own fate and that of the universe.